在会话中检查单选按钮的问题[关闭]

i want radio buttons remain selected across all pagination. For taht

I have collected the checked value in pagination at the top of page.

But it is not working well.

What is wrong with this code ?

This is how i get selected value of radio button in session

session_start();
if(isset($_POST['answer'])) {
    $_SESSION['answer'] = $_POST['answer'];
}

This is my php code

<input type="radio"  name="answer" value="yes" <?php if(isset($_SESSION['answer'])=='yes') {echo "checked"; }?> />
<input type="radio"  name="answer" value="no" <?php if(isset($_SESSION['answer'])=='no') {echo "checked"; }?> />
<input type="radio"  name="answer" value="yes1" <?php if(isset($_SESSION['answer'])=='yes1') {echo "checked"; }?> />
<input type="radio"  name="answer" value="yes2" <?php if(isset($_SESSION['answer'])=='yes2') {echo "checked"; }?> />

It gives me error(notice) like answer is undefined index.

isset() returns true or false. Your if statement should be, for example:

if (isset($_SESSION['answer']) && $_SESSION['answer'] == 'yes')

Try with:

$values = array('yes', 'no', 'yes1', 'yes2');
foreach ( $values as $value ) {
  $checked = isset($_SESSION['answer']) && $_SESSION['answer'] == $value ? 'checked="checked"' : '';
  echo '<input type="radio"  name="answer" value="' . $value . '" ' . $checked . '/>';
}

<input type="radio"  name="answer" value="yes" <?php if($_SESSION['answer']=='yes') { ?> checked="checked" <?php }?> />
<input type="radio"  name="answer" value="no"  <?php if($_SESSION['answer']=='no') { ?> checked="checked" <?php }?> />
<input type="radio"  name="answer" value="yes1" <?php if($_SESSION['answer']=='yes1') { ?> checked="checked" <?php }?> />
<input type="radio"  name="answer" value="yes2" <?php if($_SESSION['answer']=='yes2') { ?> checked="checked" <?php }?> />

please use this html